TABLE 1.
Pharmacokinetic parameters of gatifloxacin (400 mg orally) for different treatments determined by HPLCa
| Treatment | Cmax (μg/ml/70 kg) | Tmax (h) | Tlag (h) | Half-life (h) | MRT (h) | AUC0–∞ (μg · h/ml/70 kg) | Total urinary recovery (% of dose) | Renal clearance (ml/min/1.73 m2) | VSS (liters/70 kg) |
|---|---|---|---|---|---|---|---|---|---|
| 1A | 3.8 ± 0.5 | 1.4 ± 0.8 | 0.23 ± 0.02 | 8.6 ± 1.4 | 11.3 ± 1.9 | 33.5 ± 5.9 | 82.5 ± 6.0 | 164 ± 37 | 121 ± 13.4 |
| 1B | 2.1 ± 1.2b | 1.8 ± 1.0 | 0.22 ± 0.03 | 8.4 ± 1.9 | 12.0 ± 3.1 | 19.4 ± 6.9b | 53.2 ± 19b | 176 ± 30 | 260 ± 158b |
| 1C | 1.2 ± 0.4b | 1.6 ± 0.7 | 0.20 ± 0.06 | 9.5 ± 2.0 | 13.2 ± 3.0c | 11.9 ± 3.3b | 35.9 ± 10b | 195 ± 30c | 421 ± 156b |
| 2D | 3.4 ± 0.9 | 1.7 ± 0.7 | 0.23 ± 0.02 | 7.5 ± 1.2 | 10.3 ± 1.4 | 31.4 ± 3.4 | 84.2 ± 7.7 | 165 ± 20 | 115 ± 17 |
| 2E | 3.3 ± 1.4 | 1.5 ± 1.1 | 0.22 ± 0.03 | 7.0 ± 1.2 | 9.8 ± 1.3 | 25.9 ± 5.3b | 73.1 ± 11c | 175 ± 17 | 139 ± 47b |
| 2F | 3.5 ± 1.1 | 1.6 ± 1.0 | 0.21 ± 0.07 | 7.0 ± 0.9 | 10.0 ± 1.3 | 31.3 ± 4.0 | 79.8 ± 5.2 | 157 ± 14 | 111 ± 12 |
a
Treatment groups were as follows: 1A, gatifloxacin alone; 1B, aluminum magnesium hydroxide 2 h before gatifloxacin; 1C, aluminum magnesium hydroxide concomitant with gatifloxacin; 2D, gatifloxacin alone; 2E, aluminum magnesium hydroxide 2 h after gatifloxacin; 2E, aluminum magnesium hydroxide 4 h after gatifloxacin. Values are means ± standard deviations. MRT, mean residence time; Tlag, time between drug administration and beginning of absorption.
b
P < 0.01 versus gatifloxacin alone.
c
P < 0.05 versus gatifloxacin alone.